Jumping Bristletail

Description:

A quite beautiful Jumping Bristletail of about 1 cm in body length. It has 3 "tails" which are the median epiproct and two shorter cerci. The eyes are large, compound and contiguous on the top of the head. It is also humpbacked over the thorax. This makes it a member of the Order Archaeognatha, Family Machilidae. These are very primitive insects, little changed from the early Devonian fossils. They can jump about, springing off with their abdominal muscles. They also have many detachable scales, making them hard to hang onto by a predator.

Habitat:

This one was found at night on a low brick wall in the garden, semi-rural residential area, San Cristobal de Las Casas, Chiapas, Mexico, 2,200 meters.

Notes:

The Jumping Bristletails used to be classified with the Silverfish and Firebrats in the Order Thysanura. Now, the Bristletails are in the Order Archaeognatha and the Silverfish and Firebrats are in the Order Zygentoma. The Bristletails are also unique to all other insects in having only 1 knuckle-like bone (the Condyle) connecting the mandibles to the head. (All other insects have two condyles, including the Zygentoma). The Bristletails also have little articulated styli on the 2nd and 3rd pair of coxae and on sternites 2 through 9 (not visible in these pictures) which some evolutionists believe to be remains of legs. Their mating strategy is also primitive, in that the male produces spermatophores which he leaves on the ground for the female to pick up. Although in many species there is some courtship behavior involved. Another unique feature of these insects is that they continue to molt even after reaching reproductive adulthood.